Introduction to monitoring data
There are three types of data stored in this section and these are outlined below.
1. Monitoring data
There are over 1500 sites across the UK that monitor air quality. They are organised into networks that gather a particular kind of information, using a particular method. There are two major types - automatic and non-automatic networks. The Monitoring Networks section provides further network information. Download data from the networks using the Data Selector Tool or download raw automatic data using the preformatted files link.
2. Descriptive statistics
For each monitoring site you can select a range of statistics which are relevant to the particular monitoring method. Basic statistics are annual mean, maximum and minimum values, with daily means, monthly means and a range of percentile values available where these are meaningful.
3. Exceedance statistics
Exceedance statistics provide information about concentrations above a specific threshold value. The exact concentration and the metric used varies by pollutant and purpose. A selection of commonly used examples are the UK Air Quality Objectives, EU Limit and Target Values, Critical Loads, the health-effects based system of four bands and a 1-10 index and the Indicators of Sustainable development - the average number of days per site on which pollution levels were above National Air Quality Standards.
You can select any of these exceedance statistics for a range of time periods, pollutants and locations.
Information on uk-air.defra.gov.uk is published by Defra and the Devolved Administrations under the Open Government Licence (OGL) and subject to the terms described in the "licence" or "constraints" of the OGL, except where otherwise noted. Under the OGL you are free to:
- copy, publish, distribute and transmit the information
- adapt the information
- exploit the information commercially and non-commercially for example, by combining it with other information, or by including it in your own product or application
You must, where you do any of the above, acknowledge Defra and uk-air.defra.gov.uk as the source of the information by including the following attribution statement in reports, web pages or derived data products and, where possible, provide a link to the OGL licence.
© Crown 2020 copyright Defra via uk-air.defra.gov.uk, licenced under the Open Government Licence (OGL).
The data and information made available through on this website is subject to Crown copyright protection unless otherwise indicated. Read the Crown copyright page for more information. See also https://www.gov.uk/support/terms-conditions.
This website is maintained and hosted by Ricardo Energy & Environment on behalf of Defra and the Devolved Administrations.